Synchronized light control over a wireless network

ABSTRACT

A light control and data interface module (LCDIM) is used to control an LED based illumination device. The LCDIM includes a transceiver that receives communication signals from one or more sensor modules. The signals may include an indication of an identity of the one or more sensor modules and elapsed time since a triggering event was detected. One or more processors are configured to receive the communication signal and to determine a delay time to trigger a lighting control response. The one or more processors are further configured to cause the transmission of a command signal to a power converter coupled to the LCDIM to implement the lighting control response.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. application Ser. No.15/055,298, filed Feb. 26, 2016, which, in turn, claims priority under35 USC 119 to U.S. Provisional Application No. 62/126,341, filed Feb.27, 2015, and to U.S. Provisional Application No. 62/145406, filed Apr.9, 2015, all of which are incorporated by reference herein in theirentireties.

TECHNICAL FIELD

The described embodiments relate to LED based illumination devices thatinclude Light Emitting Diodes (LEDs).

BACKGROUND

The use of LEDs in general lighting is becoming more desirable.Typically, LED illumination devices are standalone units. It isdesirable, however, to control a plurality of LED illumination devices.

SUMMARY

A light control and data interface module (LCDIM) is used to control anLED based illumination device. The LCDIM includes a radio frequencytransceiver that receives communication signals from one or more sensormodules. The signals ma include an indication of an identity of the oneor more sensor modules and elapsed time since a triggering event wasdetected. One or more processors are configured to receive thecommunication signal and to determine a delay time to trigger a lightingcontrol response. The one or more processors are further configured tocause the transmission of a command signal to a power converter coupledto the LCDIM to implement the lighting control response.

In one implementation, a light control and data interface moduleincludes one or more processors; a transceiver configured to receive afirst communication signal from one or more sensor modules, the firstcommunication signal including an indication of an identity of the oneor more sensor modules and a first elapsed time since a triggering eventwas detected by the one or more sensor modules; and a lion-transitory,computer readable medium storing instructions that when executed by theone or more processors cause the one or more processors to: receive thefirst communication signal from the transceiver; determine a delay timeto trigger a lighting control response based on a difference between adesired delay time to trigger the lighting control response and thefirst elapsed time; and transmit a command signal that implements thelighting control response to a power converter coupled to the lightcontrol and data interface module after the delay time to trigger thelighting control response has elapsed, wherein the power converter isconfigured to supply an electrical current to an LED based light enginein response to the command signal.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts a lighting control network in an exemplary, non-limitingembodiment.

FIG. 2 depicts an exemplary LED based illumination device that includesa Light Control and Data Interface Module (LCDIM) configured to supplyelectrical power to an LED based light engine.

FIG. 3 depicts an exemplary sensor module that may be included in theLED based illumination device.

FIG. 4 depicts an environment illuminated by a plurality of LED basedillumination device

FIG. 5 depicts a lighting control network in which a mobile electronicdevice broadcasts a signal that includes, e.g., an indication of theidentity of sensor, an indication of the identities of each of the LEDbased illumination devices participating in the group, and at least onelighting control rule.

FIGS. 6 and 7 depict a top view and a side view, respectively, of an LEDbased illumination device including a LCDIM.

FIG. 8 depicts an exploded view illustrating components of LED basedillumination device as depicted in FIGS. 2-3.

FIG. 9 illustrates a cross-sectional view of an LED based light engine.

FIG. 10 depicts a cross-sectional illustration of an LED basedillumination device including optical sensors located on LED based lightengine outside the light conversion cavity.

FIG. 11 depicts a perspective view of a luminaire including an LED basedillumination device with a rectangular form factor.

FIG. 12 depicts a perspective view of a luminaire including an LED basedillumination device with a circular form factor.

FIG. 13 depicts a side view of a luminaire including an LED basedillumination device integrated into a retrofit lamp device.

DETAILED DESCRIPTION

Reference will now be made in detail to background examples and someembodiments of the invention, examples of which are illustrated in theaccompanying drawings.

FIG. 1 depicts a lighting control network 10 in an exemplary,non-limiting embodiment. Lighting control network 10 is configured as awireless network (e.g., Bluetooth Smart, Bluetooth Low Energy, etc.)that includes environmental sensor module 50 and LED based illuminationdevices 100A-D. In one aspect, the LED based illumination devicesrespond to signals received from one or more environmental sensors basedon rules stored on board each LED based illumination device. In thismanner, the intelligence of the lighting control network resides in theLED based illumination devices, but the signals that trigger responsesfrom the illumination devices originate from one or more sensorscommunicatively coupled to the LED based illumination devices.

In another aspect, the response of each individual LED basedillumination device to a particular sensor signal is synchronized intime with the responses of every other individual LED based illuminationdevice within a predefined group to ensure a coordinated, uniformillumination response. By synchronizing the response of each LED basedillumination device in a group, a desirable lit effect is achieved. Insome embodiments, this is achieved without resorting to synchronizationof every networked device (i.e., sensor modules and LED basedillumination devices) to a network time reference. This reduces networkoverhead associated with maintaining time across each device in thenetwork. In some other embodiments, a global time base is employed andthe LED based illumination devices in a lighting control group maintainan accurate measure of time, for example, by periodic recalibration witha global time reference. A trigger signal (e.g., communication from anenvironmental sensor) requiring a synchronized response among any numberof LED based illumination devices in a lighting control network simplyneeds to refer to a particular time of the triggering event referencedto the global time base. Since all LED based illumination devices aresynchronized to the global time base, their respective responses to thetrigger signal will also be synchronized in time based on pre-programmedrules associated with the response of each LED based illumination deviceto the triggering event.

The communication of signals between sensor module 50 and each LED basedillumination device 100A-D may take a different amount of time in awireless network. The wireless network may require multipletransmissions of the same signal to reach each LED based illuminationdevice in the group. The latency associated with each transmission maybe different. Without synchronization, different LED based illuminationdevices may initiate an illumination response to the received sensorsignals at different times. This may result in a visible lack ofuniformity in the lit effect. One manifestation of this effect iscommonly referred to as a “popcorn” response where lights in a roomappear to change intensity in a random pattern that users findunpleasant.

In the lighting control network 10 depicted in FIG. 1, an environmentalsensor module 50 detects an environmental event (e.g., presence,movement, sound, temperature, vibration, user control, etc.) andwirelessly transmits a signal 51 that includes an indication of theidentity of the sensor module, an indication of the triggering event,and an amount of time that has elapsed between the recognition of thetriggering event by the sensor module and the time of transmission ofthe signal 51. This time, T_(LAG1), represents an approximation of thelatency associated with the communication of the triggering event by thesensor module. Signal 51 is broadcast wirelessly and is received by LEDbased illumination devices 100A, 100B, and 1000, but not LED basedillumination device 100D.

In some embodiments, successive transmissions of signals indicative ofthe triggering event may be made. Each successive transmission by sensormodule 50 includes the identity of the sensor module, the indication ofthe triggering event, and an amount of time that has elapsed between therecognition of the triggering event by the sensor module and the time oftransmission associated with each successive signal. In this manner, anysignal transmission by sensor module 50 indicative of a triggering eventincludes an approximation of the latency associated with thecommunication of the triggering event by the sensor module.

In turn, LED based illumination device 100A broadcasts signal 52 toeffectively relay the message from sensor module 50. To maintainsychronization, signal 52 includes an indication of the identity of thesensor module 50, the indication of the triggering event, and an amountof time that has elapsed between the recognition of the triggering eventby the sensor module and the time of transmission of the signal 52. Thistime, T_(LAG2), represents an approximation of the latency associatedwith the communication of the triggering event by the sensor module andthe latency associated with the communication of the triggering event byLED based illumination device 100A. Signal 52 is broadcast wirelesslyand is received by LED based illumination devices 100D.

Similarly, LED based illumination device 100B broadcasts signal 53 toeffectively relay the message from sensor module 50. To maintainsychronization, signal 53 includes an indication of the identity of thesensor module 50, the indication of the triggering event, and an amountof time that has elapsed between the recognition of the triggering eventby the sensor module and the time of transmission of the signal 53. Thistime, T_(LAG3), represents an approximation of the latency associatedwith the communication of the triggering event by the sensor module andthe latency associated with the communication of the triggering event byLED based illumination device 100B. In addition, LED based illuminationdevice 100C broadcasts signal 54 to effectively relay the message fromsensor module 50. To maintain sychronization, signal 54 includes anindication of the identity of the sensor module 50, the indication ofthe triggering event, and an amount of time that has elapsed between therecognition of the triggering event by the sensor module and the time oftransmission of the signal 54. This time, T_(LAG4), represents anapproximation of the latency associated with the communication of thetriggering event by the sensor module and the latency associated withthe communication of the triggering event by LED based illuminationdevice 100C.

LED based illumination device 100D receives signals 52, 53, and 54 thateach communicate the same triggering event along with the latencyassociated with each respective communication path. In some embodiments,LED based illumination device 100D receives the first message indicativeof the triggering event and ignores the subsequent messages associatedwith the same triggering event (e.g., subsequent messages referencingthe same event number). Assuming that signals 52 is received first, itfollows that signals 53 and 54 are ignored.

In turn, LED based illumination device 100D broadcasts signal 55 toeffectively relay the message from sensor module 50. To maintainsychronization, signal 55 includes an indication of the identity of thesensor module 50, the indication of the triggering event, and an amountof time that has elapsed between the recognition of the triggering eventby the sensor module and the time of transmission of the signal 55. Thistime, T_(LAG5), represents a summation of the latency associated withthe communication of the triggering event by the sensor module, thelatency associated with the communication of the triggering event by LEDbased illumination device 100A, and the latency associated with thecommunication of the triggering event by LED based illumination device100D.

In some embodiments, the estimate of communication latency associatedwith each message is determined based on the number of communicationhops and the elapsed time associated with each bop, in some otherembodiments, the estimate of communication latency associated with eachmessage is determined based on a pre-determined calibration table thatassigns a particular latency to each pair of nodes in the lightingcontrol network. In some other embodiments, the estimate ofcommunication latency associated with each message is determined basedon the number of packets buffered at each receiving node.

In general, communication latency may be expressed directly as anelapsed time, or alternatively an alternative, indirect indication oftime may be employed.

In one aspect, the delays may be dynamically set based on the nodesreceiving various packets with delays. For example, a node will likelysee a re-broadcast of its original message with some added delay. As thenode initiated the message, the node will be aware of the actual delayand, accordingly, can determine the error in delay. If the error is toolarge, e.g., greater than a threshold, the node may report the errorback to the network, which may then adjust parameters to minimize theerror. The dynamically set delay may be particularly useful e.g. to setup the network up initially, i.e. program in the node delays.

In another aspect, each of the LED based illumination devices 100A-D isprogrammed to initiate a change in the light emitted from each LED basedillumination device after a fixed amount of time has elapsed from themoment that the triggering event was recognized by the sensor module. Inone example, each of the LED based illumination devices 100A-D isprogrammed to initiate a fade-on after 500 milliseconds has elapsed fromthe moment that the triggering event was recognized by the sensormodule. In addition, T_(LAG1) is 200 milliseconds. T_(LAG2) is 400milliseconds, T_(LAG3) is 420 milliseconds, and T_(LAG4) is 450milliseconds. LED based illumination devices 100A-C receive signal 51and determine the difference between the desired 500 millisecond lag andthe 200 millisecond latency associated the communication of signal 51 bysensor module 50. As a result, LED based illumination devices 100A-Callow 300 milliseconds to elapse between receiving signal 51 andinitiating the fade-on of each respective light emitting device.Similarly, LED based illumination device 100D receives signal 52 anddetermines the difference between the desired 500 millisecond lag andthe 400 millisecond latency associated the communication of signal 52 byLED based illumination device 100A. As a result, LED based illuminationdevice 100D allows 100 milliseconds to elapse between receiving signal52 and initiating the fade-on of the light emitting device. In thismanner, the illumination response by each of LED based illuminationdevices 100A-D is initiated at the same time despite the fact that oneor more of the LED based illumination devices receiving signalsindicative of the triggering event at one or more different times.

In general, the initiation of a change in the light emitted from eachLED based illumination device may be coordinated with the other LEDbased illumination devices in the lighting control network in anydesired manner. For example, all of the LED based illumination devicesin the lighting control network may be configured to fade to aparticular light level starting at the same time. In some otherexamples, one or more of the LED based illumination devices in thelighting control network may be configured to fade to a particular lightlevel starting at different, predetermined elapsed times, for example,to progressively “turn on” lights down a hallway.

In a further aspect, if an LED based illumination device does notreceive the trigger signal from the environmental sensor input untilafter the predetermined response time has already elapsed, analternative, “catch-up,” response may be used. For example, an LED basedillumination device may not receive a signal indicative of the triggerevent until after die desired 500 millisecond lag. The alternative,catch-up response utilized may depend on amount of time between thespecified response time and the event. For example, if the time betweenthe specified response time and the event is relatively small comparedto the fade time, e.g., a threshold of less than 25% of the fade timemay be used, the LED based illumination device may reduce the fade timeso that the LED based illumination device reaches the final intensity atthe same time as the other LED based illumination devices. In anotherexample, if the time between the specified response time and the eventis greater than the define threshold, the LED based illumination devicemay turn on at a slower fade rate (e.g., 2× specified time) to make thelate transition as unobtrusive as possible.

FIG. 2 depicts an exemplary LED based illumination device 100 with areflector 150 and that includes a Light Control and Data InterfaceModule (LCDIM) 1.10 configured to supply electrical power to an LEDbased light engine 160. In addition, LCDIM 110 also integrates lightcontrol, power conversion, data acquisition, data processing, andcommunication capability.

In the embodiment depicted in FIG. 2, LCDIM 110 includes an LED driver121, one or more power converter 123, one or more radio frequencytransceiver 129, one or more processors 122, one or more memory 126, andone or more timer 127 configured to communicate over bus 128.

FIGS. 6 and 7 depict a top view and a side view, respectively, of an LEDbased illumination device 200 including a LCDIM. An example of such alighting device is the Xicato Intelligent Module (XIM) manufactured byXicato, Inc., San Jose, Calif. (USA).

FIG. 8 depicts an exploded view illustrating components of LED basedillumination device 200 as depicted in FIG. 2. As depicted in FIG. 8,LED based illumination device 200 includes LED based light engine 160,LCDIM 110, including primary ECB 120 and peripheral ECB 130, heat sink101, mounting plate 102, and housing 103.

The assembled LED based illumination device 200 mechanically integratesthe LED based light engine with the LCDIM within a common housing.However, in general, one or more components of LED based illuminationdevice 200 may be mechanically separated from the others. In theseembodiments, one or more components may be separately located on a lightfixture and electrically coupled to the other components by suitablewiring and connectors. In some embodiments, LED based light engine 160is assembled within a simple housing to facilitate attachment to a heatsink. An example of such a lighting device is the Xicato Thin Module(XTM) manufactured by Xicato, Inc., San Jose, Calif. (USA). In thisexample, one or more components of LCDIM 110 are packaged in a separatehousing, and this assembly is electrically coupled to the LED basedlight engine by a wired connection.

It should be understood that as defined herein an LED based illuminationdevice is not an LED, but is an LED light source or fixture or componentpart of an LED light source or fixture. As depicted in FIG. 8, LED basedillumination device 200 includes an LED based light engine 160configured to generate an amount of light. LED based light engine 160 iscoupled to heat sink 101 to promote heat extraction from LED based lightengine 160. Primary ECB 120 and peripheral ECB 130 are shaped to fitaround heat sink 101. LED based light engine 160, primary ECB 120,peripheral ECB 130, and heat sink 101 are enclosed between mountingplate 102 and housing 103. An optional reflector retainer (not shown iscoupled to housing 103. The reflector retainer is configured tofacilitate attachment of different reflectors to the LED basedillumination device 200.

In some embodiments, it is advantageous to separate the electronicfunctionality of LCDIM 110 across two or more electrical circuit boards,as depicted in FIG. 8, to minimize logistical complexity. For example,in a network of LED based illumination devices, certain devices mayinclude different functionality than others. Common functionality isincluded on the primary ECB associated with each device. In this mannereach manufactured device includes the same primary ECB. However,differing functionality is included in a different peripheral ECB. Inthis manner, one of more different devices may include differentperipheral ECBs. Many different configurations may be contemplated,however, in general, the electronic functionality of LCDIM 110 asdescribed herein may be distributed across any number of components inany suitable manner.

In the embodiment depicted in FIG. 2, LED driver 121 is configured tosupply power to one or more LEDs of the LED based light engine 160 overa wired connection 124 between LCDIM 110 and LED based light engine 160.In one embodiment, LED driver 121 is a direct current to direct current(DC/DC) power converter. The DC/DC power converter receives electricalpower signals 111 (e.g., 48 Volt supply voltage) supplied to LCDIM 110.The electrical power signals 111 are processed by the DC/DC powerconverter to generate electrical current 125 supplied to the LEDs of LEDbased light engine 160. In some other embodiments, driver 121 isconfigured as an AC/DC power converter configured to convert AC inputpower signals to DC current signals supplied to the LEDs of LED basedlight engine 160, in some other embodiments, driver 121 is configured asan AC/AC power converter configured to convert AC input power signals toAC current signals supplied to the LEDs of LED based light engine 160(e.g., when LED based light engine 160 includes AC LEDs).

In another aspect, LCDIM 110 includes a power converter 123 configuredto supply low voltage electrical power signals to the components ofLCDIM 110 in this manner, electrical power signals 111 can be used tosupply electrical power to driver 121 and electrical power to the lowvoltage components of LCDIM 110 after power conversion by powerconverter 123. In some embodiments, power converter 123 is a DC/DC powerconverter that steps down the voltage of electrical power signals 111 toa low voltage range (e.g., less than five volts) suitable for poweringthe electronic circuitry of LCDIM 110.

LCDIM 110 includes a wireless communications interface. In someembodiments the wireless communications interface is configured totransmit and receive communications signals 138 (e.g., signals 51 and52). The wireless communications interface includes a wirelesstransceiver 129 operable in accordance with a wireless communicationsprotocol, and one or more associated antennas 136 mounted to LED basedillumination device 100. Any suitable wireless communications protocolmay be contemplated, (e.g., Bluetooth Smart, Bluetooth Low Energy,802.11, Zigbee, cellular modem, etc.).

In some embodiments, one or more antennas are mounted to the externalfacing surface(s) of LED based illumination device 100 to maximizecommunication efficiency between LED based illumination device 100 and aremotely located communications device (e.g., another LED basedillumination device, a sensor module, a mobile phone, a router, or otherdigital system). In sortie embodiments, an antenna is integrated intothe peripheral ECB 130. In some other embodiments, the antenna isintegrated into the primary ECB 120. In some other embodiments, theantenna is integrated into housing 103, for example, by molding theantenna into the housing structure or attaching the antenna to a surfaceof the housing structure. In some other embodiments, the antenna isintegrated into the mounting board of the LED based light engine 160.

As depicted in FIG. 2, LCDIM 110 includes an internal communications bus128 coupled to various components including processor 122, memory 126,timer 127, power convener 123, transceiver 129, and driver 121.

In a further aspect, memory 126 stores identification data, operationaldata such as temperature history, current history, etc. For example, anidentification number, a network security key, commissioninginformation, etc. may be stored on memory 126.

In another further aspect, LCDIM 110 includes processor readableinstructions stored on memory 126 that cause processor 122 to 1) receivewireless signal 51 from sensor module 50 that includes an indication ofthe latency associated with the recognition of the triggering event andthe communication of signal 51, 2) determine a delay time to trigger alighting control event based a difference between the latency and adesired delay time between the triggering event and the initiation ofthe lighting control response, and 3) transmit a command signal thatinitiates the lighting control response to a power converter after thedelay time has elapsed (e.g., as measured by timer 127). As depicted inFIG. 2, driver 121 is configured to supply an electrical current 125 toLED based light engine 160 in response to a command signal communicatedover bus 128. As depicted in FIG. 2, the desired delay time between thetriggering event and the lighting control response is stored in memory126. It, should be understood that the processor 122 may be one or moreprocessors communicating with each other. For example, one processor mayreceive and decode the signal from the sensor module 50, while a secondprocessor may control the light response, e.g., turning the LED driveron or off, by transmitting the command signal.

In some embodiments, the lighting control response is determined basedat least in pan on the indication of an identity of the sensor module.By way of non-limiting example, the lighting control response mayinclude any of a fade-on rate, a target intensity level, a persistencetime, and a fade-off rate.

In another further aspect, LCDIM 110 includes processor readableinstructions stored on memory 126 that cause processor 122 to receivewireless signal 51 from sensor module 50 and wirelessly communicatesignal 52 over transceiver 129. The processor readable instructionsstored on memory 126 also cause processor 122 to determine the elapsedtime between detection of the triggering event by sensor module 50 andthe communication of signal 52 by determining the sum of the latencyassociated with communication of the triggering event by sensor module50 and the time elapsed between the receiving of signal 51 and thetransmitting of signal 52.

FIG. 3 depicts an exemplary sensor module 50 that includes anenvironmental sensor 139, a timer 131, a processor 132, a radiofrequency transceiver 135, and a memory 133, configured to communicateover bus 134.

Sensor module 50 includes processor readable instructions stored onmemory 133 that cause processor 132 to recognize a triggering eventsensed by sensor 139 and communicate a signal 51 indicative of anidentity of the sensor module 50 and a time elapsed between therecognition of the triggering event and the transmission of signal 51(e.g., as measured by timmer 131). By way of non-limiting example, theindication of the identity of the sensor module includes any of a sensoridentification number, an indication of a group of which the sensormodule is a part, an indication of the type of sensor, an indication ofan address of the sensor module on a wireless network, and an indicationof the triggering event.

Sensor module 50 includes a wireless communications interface configuredto transmit communications signals from sensor module 50. The wirelesscommunications interface includes a wireless transmitter 135 operable inaccordance with a wireless communications protocol, and one or moreassociated antennas mounted to sensor module 50. In one example, sensormodule 50 is operable in accordance with the Bluetooth Smart protocol tobroadcast signal 51. As described herein, in one specificimplementation, for example, sensor module 50 is operable in accordancewith an iBeacon protocol to broadcast information with which locationmay be determined.

By way of non-limiting example, sensor 139 may include any of a presencesensor, a light sensor, an acoustic sensor, a vibration sensor, ahumidity sensor, a pressure sensor, a gas monitoring sensor (e.g., CO2,CO, etc.), and any associated interface electronics. Sensor 139 mayinclude one or more occupancy sensors, motion sensors, ambient lightsensors, temperature sensors, cameras, microphones, visual indicatorssuch as low power LEDs, ultrasonic sensors, and photodetectors.

In some examples, sensor module 50 is configured to transmit (and LCDIM110 is configure to receive) a communication signal that indicates theidentity of the sensor module and an indication that a triggering eventwas not detected by the sensor module. This communication may beemployed as part of an on-going diagnosis of network health.

In some examples, sensor module 50 is further configured to retransmit acommunication signal indicative of a triggering event multiple times. Inthese embodiments, a subsequent communication signal includes theindication of the identity of the sensor module and an elapsed timesince the triggering event was detected by the sensor module. It followsthat at each successive transmission, a greater amount of time elapsesfrom the triggering event. In some embodiments, the communication signalincludes an indication of the cumulative number of successivecommunications from the sensor module indicating the triggering eventdetected by the sensor module (i.e., retransmission number).

In some embodiments, the communication signals of lighting controlnetwork 10 are encrypted.

In some embodiments, it is desireable to locate sensors in areas exposedto light emitted from the LED based light engine 160. FIG. 10 depicts across-sectional illustration of an LED based illumination deviceincluding optical sensors 180 and 181 located on LED based light engine160 outside the light conversion cavity. In some other examples, asensor (e.g., silicon photo diode) is located within the lightconversion cavity.

In some other examples, sensors may be mounted to a reflector assemblythat is electrically coupled to peripheral ECB 130 (e.g., via anelectrical connector, contacts, or inductively coupled).

FIG. 10 depicts a reflector assembly including sensing capabilitydetachably mounted to an LED based illumination device in oneembodiment. The reflector housing includes a reflector 201, sensors 204,and an electronics interface board 213. In the depicted embodiment, thereflector housing includes an outward facing surface. In other words, atleast one surface of the reflector housing faces away from the lightsource of LED based illumination device 200 and toward the environmentilluminated by LED based illumination device 200. Sensors (e.g., sensor204) are mounted in the reflector housing along the outward facingsurface. In this manner, the sensors are sensitive to physical signalsdirected toward LED based illumination device 200. Signals generated bythe sensors are communicated to an electrical interface board 213coupled to the reflector housing for further processing andcommunication to LED based illumination device. The sensor messages maybe sent from the reflector 201 to the LED illumination device 200wirelessly using a protocol such as Bluetooth Smart. In this manner, thesensor messages may be received not only by the local LED illuminationdevice 200, but by nearby LED illumination devices as well.

Reflector 201 includes an input port configured to receive a firstamount of light emitted from the LED based illumination device 200 andan output port through which light passes toward the environment. Thereflecting surface(s) of reflector 201 are configured to redirect atleast a portion of the light emitted from the LED based illuminationdevice toward the output port.

In the depicted embodiment, the reflector assembly is communicativelycoupled to peripheral ECB 130 of the LED based illumination device by aconnector 220, and the reflector assembly is configured to transmit andreceive communications signals to and from the peripheral ECB 130. Inone embodiment, the electronics interface board 213 is configured toroute communications between the sensor 204 and the LED basedillumination device over a wired interface, such as a four pin interfaceincluding two power pins and two communication pins (e.g. 12Cinterface). In some other embodiments, electrical interface board 213includes a coiled conductor and peripheral ECB 130 includes acomplementary coiled conductor. The conductors are configured to form aninductive coupling operable in accordance with a near fieldcommunications (NFC) protocol. In this manner, signals may be passedbetween the reflector assembly and LED based illumination device.

Many different types of sensors may be mounted to the reflectorassembly. By way of non-limiting example, one or more occupancy sensors,ambient light sensors, temperature sensors, cameras, microphones, visualindicators such as low power LEDs, ultrasonic sensors, vibrationsensors, pressure sensors, and photodetectors ma be mounted to thereflector assembly.

In some embodiments, additional sensors may be electrically coupled tothe reflector assembly and data signals 211 generated by these externalsensors are communicated to the electronic interface board 213. Externalsensors may also be directly connected to ECB 130 or ECB 120 in LEDbased illumination device 200. The collected data may then becommunicated to LED based illumination device as described hereinbefore.

In general, any outwardly facing surface of LED based illuminationdevice 100 is suitable for any sensor collecting data from theenvironment illuminated by LED based illumination device 100. However,in some embodiments, one or more sensors may be located in areas of theLED based illumination device 100 that are not necessarily exposed tothe environment illuminated by LED based illumination device 100. Forexample, one or more temperature sensors, vibration sensors, andpressure sensors may coupled to peripheral ECB 130 or primary ECB 120 tomonitor environmental parameters such as temperature, etc., near LEDbased illumination device 100. For example, a temperature sensor may bemounted close to electronic components of peripheral ECB 130 or primaryECB 120 to monitor operating temperatures to minimize component failure.

FIG. 4 depicts an environment 141 illuminated by LED based illuminationdevice 100A-H. In addition, a sensor module 50 is located in environment141 and is configured to sense a physical property of the environment(e,g., presence, light intensity, motion, etc.). In addition, FIG. 4depicts a mobile electronics device 140 (e.g., mobile phone, tabletcomputer, etc.) that includes a camera module 140 c and associatedsoftware to identify the presence of LED based illumination devices100A-H. The camera module 140 c and associated software may alsoidentify the presence of sensor module 50 within environment 141 aswell, e.g., with an LED, such as a near infrared LED on the sensor or bydetecting a predetermined modulation of light emitted by one or more ofthe LED based illumination devices 100A-H.

In one example, it may be desirable to group LED based illuminationdevices 100A-H and control the light emitted from the LED basedillumination device 100A-H based on triggering events sensed by sensormodule 50.

In one aspect, mobile communication device 140 is configured to generateand communicate instructions to LED based illumination devices 100A-Hthat define Light control rules that govern the response of each of theLED based illumination devices 100A-H to a signal received from sensormodule 50.

As depicted in FIG. 5, mobile electronic device 140 broadcasts signal142. Signal 142 includes an indication of the identity of sensor module50 (Sensor ID), an indication of the identities of each of the LED basedillumination devices participating in the group (e.g., LED basedillumination devices 100A-H) (Target ID), and at least one lightingcontrol rule (Rule). The lighting control rule includes at least oneparameter that defines at least a portion of the light control responseof each. LED based illumination device to a communication received fromsensor module 50. By way of non-limiting example, a parameter definingat least a portion of the light control response may include any of afade-on rate, a target intensity level, a persistence time, and afade-off rate.

As depicted in FIG. 5, signal 142 may not directly reach all of the LEDbased lighting control devices. In the depicted example, LED basedillumination devices 100A-C receive signal 142, and transmit signals143-145, respectively. Signals 143-145 include the contents of signal142. In this manner, LED based illumination device 100D receives theprogramming information contained in signal 142.

Each of the LED based illumination devices 100A-D compare their ownidentities (e,g., MAC address, network ID, etc.) with the targetidentities included in signal 142. If there is match, the LED basedillumination device writes the sensor identity and light control rule(s)to their respective memories (e.g., memory 126 depicted in FIG. 2). Inthis manner, each LED based illumination device is configured to respondto communications received from the appropriate sensor modules andrespond in accordance with the programmed light control rules.

In this manner, a mobile communication device may be employed toflexibly program groups of LED based illumination devices to respond ina synchronized manner to one or more environmental sensors.

Although, programming information may be communicated to one or more LEDbased illumination devices by a mobile electronic device, in general,any suitable electronic device (e.g., building management server,networked computer, etc.) may be employed to communicate programinginformation.

FIG. 9 is illustrative of LED based light engine 160 in one embodiment.LED based light engine 160 includes one or more LED die or packaged LEDsand a mounting board to which LED die or packaged LEDs are attached, inaddition. LED based light engine 160 includes one or more transmissiveelements (e.g., windows or sidewalls) coated or impregnated with one ormore wavelength converting materials to achieve light emission at adesired color point.

As illustrated in FIG. 9, LED based light engine 160 includes a numberof LEDs 162A-F mounted to mounting board 164 in a chip on board (COB)configuration. The spaces between each LED are filled with a reflectivematerial 176 (e.g., a white silicone material). In addition, a dam ofreflective material 175 surrounds the LEDs 162 and supports transmissiveelement 174, which may be, e.g., a plate. The space between LEDs 162 andtransmissive element 174 is filled with an encapsulating opticallytranslucent mated& 177 (e.g., silicone) to promote light extraction fromLEDs 162 and to separate LEDs 162 from the environment. In the depictedembodiment, the dam of reflective material 175 is both the thermallyconductive structure that conducts heat from transmissive element 174 toLED mounting board 164 and the optically reflective structure thatreflects incident light from LEDs 162 toward transmissive element 174.

LEDs 162 can emit different or the same colors, either by directemission or by phosphor conversion, e.g., where phosphor layers areapplied to the LEDs as part of the LED package. The LED basedillumination device 100 may use any combination of colored LEDs 162,such as red, green, blue, ultraviolet, amber, or cyan, or the LEDs 162may all produce the same color light. Some or all of the LEDs 162 mayproduce white light. In addition, the LEDs 162 may emit polarized lightor non-polarized light and LED based illumination device 100 may use anycombination of polarized or non-polarized LEDs. In some embodiments,LEDs 162 emit either blue or UV light because of the efficiency of LEDsemitting in these wavelength ranges. The light emitted from the LEDbased illumination device 100 has a desired color when LEDs 162 are usedin combination with wavelength convening materials on transmissiveelement 174, for example. By tuning the chemical and/or physical (suchas thickness and concentration) properties of the wavelength convertingmaterials and the geometric properties of the coatings on the surface oftransmissive element 174, specific color properties of light output byLED based illumination device 100 may be specified, e.g., color point,color temperature, and color rendering index (CRI).

For purposes of this patent document, a wavelength converting materialis any single chemical compound or mixture of different chemicalcompounds that performs a color conversion function. e.g., absorbs anamount of light of one peak wavelength, and in response, emits an amountof light at another peak wavelength.

By way of example, phosphors may be chosen from the set denoted by thefollowing chemical formulas: Y3Al5O12:Ce, (also known as YAG:Ce, orsimply YAG) (Y,Gd)3Al5O12:Ce, CaS:Eu, SrS:Eu, SrGa2S4:Eu,Ca3(Sc,Ma)2Si3O12:Ce, Ca3Sc2Si3O12:Ce, Ca3SC2O4:Ce, Ba3Si6O12N2:Eti,(Sr,Ca)AlSIN3:Eu, CaAlSiN3:Eu, CaAlSi(ON)3:Eu. Ba2SiO4:Eu Sr2SiO4:Eu,Ca2SiO4:Eu, CaSc2O4:Ce, CaSi2O2N2:Eu, SrSi2O2N2:Eu, BaSi2O2N2:Eu,Ca5(PO4)3Cl:Eu, Ba5(PO4)3Cl:Eu, Cs2CaP2O7, Cs2SrP2O7, Lu3Al5O12:Ce,Ca8Mg(SiO4)4Cl2:Eu, Sr8Mg(SiO4)4Cl2:Eu, La3Si6N11:Ce, Y3Ga5O12:Ce,Gd3Ga5O12:Ce, Tb3Al5O12:C Tb3Ga5O12:Ce, and Lu3Ga5O12:Ce.

In one example, the adjustment of color point of the illumination devicemay be accomplished by adding or removing wavelength converting materialfrom transmissive element 174. In one embodiment a red emitting phosphor186 such as an alkaline earth oxy silicon nitride covers a portion oftransmissive element 174, and a yellow emitting phosphor 184 such as aYAG phosphor covers another portion of transmissive element 174.

In some embodiments, the phosphors are mixed in a suitable solventmedium with a binder and, optionally, a surfactant and a plasticizer.The resulting mixture is deposited by any of spraying, screen printing,blade coating, jetting, or other suitable means. By choosing the shapeand height of the transmissive element 174, and selecting which portionsof transmissive element 174 will be covered with a particular phosphoror not, and by optimization of the layer thickness and concentration ofa phosphor layer on the surfaces, the color point of the light emittedfrom the device can be tuned as desired.

In one example, a single type of wavelength converting material may bepatterned on a portion of transmissive element 174. By way of example, ared emitting phosphor 186 may be patterned on different areas of thetransmissive element 174 and a yellow emitting phosphor 184 may bepatterned on other areas of transmissive element 174. In some examples,the areas may be physically separated from one another. In some otherexamples, the areas may be adjacent to one another. The coverage and/orconcentrations of the phosphors may be varied to produce different colortemperatures. It should be understood that the coverage area of the redand/or the concentrations of the red and yellow phosphors will need tovary to produce the desired color temperatures if the light produced bythe LEDs 162 varies. The color performance of the LEDs 162, red phosphorand the yellow phosphor may be measured and modified by any of adding orremoving phosphor material based on performance so that the finalassembled product produces the desired color temperature.

Transmissive element 174 may be constructed from a suitable opticallytransmissive material (e.g., sapphire, quartz, alumina, crown glass,polycarbonate, and other plastics). Transmissive element 174 is spacedabove the light emitting surface of LEDs 162 by a clearance distance. Insome embodiments, this is desirable to allow clearance tier wire bondconnections from the LED package submount to the active area of the LED.In some embodiments, a clearance of one millimeter or less is desirableto allow clearance for wire bond connections. In some other embodiments,a clearance of two hundred microns or less is desirable to enhance lightextraction from the LEDs 162.

In some other embodiments, the clearance distance may be determined bythe size of the LED 162. For example, the size of the LED 162 may becharacterized by the length dimension of any side of a single, squareshaped active die area. In some other examples, the size of the LED 162may be characterized by the length dimension of any side of arectangular shaped active die area. Some LEDs 162 include many activedie areas (e.g., LED arrays). In these examples, the size of the LED 162may be characterized by either the size of any individual die or by thesize of the entire array. In some embodiments, the clearance should beless than the size of the LED 162. In some embodiments, the clearanceshould be less than twenty percent of the size of the LED 162. In someembodiments, the clearance should be less than five percent of the sizeof the LED. As the clearance is reduced, light extraction efficiency maybe improved, but output beam uniformity may also degrade.

In some other embodiments, it is desirable to attach transmissiveelement 174 directly to the surface of the LED 162. In this manner, thedirect thermal contact between transmissive element 174 and LEDs 162promotes heat dissipation from LEDs 162. In some other embodiments, thespace between mounting board 164 and transmissive element 174 may befilled with a solid encapsulate material. By way of example, siliconemay be used to fill the space. In some other embodiments, the space maybe filled with a fluid to promote heat extraction from LEDs 162.

In the embodiment illustrated in FIG. 9, the surface of patternedtransmissive element 174 facing LEDs 162 is coupled to LEDs 162 by anamount of flexible, optically translucent material 177. By way ofnon-limiting example, the flexible, optically translucent material 177may include an adhesive, an optically clear silicone, a silicone loadedwith reflective particles (e.g., titanium dioxide (TiO2), zinc oxide(ZnO), and barium sulfate (BaSO4) particles, or a combination of thesematerials), a silicone loaded with a wavelength converting material(e.g., phosphor particles), a sintered PTFE material, etc. Such materialmay be applied to couple transmissive element 174 to LEDs 162 in any ofthe embodiments described herein.

In some embodiments, multiple, stacked transmissive layers are employed.Each transmissive layer includes different wavelength convertingmaterials. For example, a transmissive layer including a wavelengthconverting material may be placed over another transmissive layerincluding a different wavelength converting material, in this manner,the color point of light emitted from LED based illumination device 100may be tuned by replacing the different transmissive layersindependently to achieve a desired color point. In some embodiments, thedifferent transmissive layers may be placed in contact with each otherto promote light extraction. In some other embodiments, the differenttransmissive layers may be separated by a distance to promote cooling ofthe transmissive layers. For example, airflow may by introduced throughthe space to cool the transmissive layers.

The mounting board 164 provides electrical connections to the attachedLEDs 162 to a power supply (not shown). In one embodiment, the LEDs 162are packaged LEDs, such as the Luxeon Rebel manufactured by PhilipsLumileds Lighting. Other types of packaged LEDs may also be used, suchas those manufactured by OSRAM (Ostar package), Luminus Devices (USA),Cree (USA), Nichia (Japan), or Tridonic (Austria). As defined herein, apackaged. LED is an assembly of one or more LED die that containselectrical connections, such as wire bond connections or stud bumps, andpossibly includes an optical element and thermal, mechanical, andelectrical interfaces. The LEDs 162 may include a lens over the LEDchips. Alternatively, LEDs without a lens may be used. LEDs withoutlenses may include protective layers, which may include phosphors. Thephosphors can be applied as a dispersion in a binder, or applied as aseparate plate. Each LED 162 includes at least one LED chip or die,which may be mounted on a submount. The LED chip typically has a sizeabout 1 mm by 1 mm by 0.5 mm, but these dimensions may vary. In someembodiments, the LEDs 162 may include multiple chips. The multiple chipscan emit light similar or different colors, e.g., red, green, and blue.The LEDs 162 may emit polarized light or non-polarized light and LEDbased illumination device 100 may use any combination of polarized ornon-polarized LEDs. In some embodiments, LEDs 162 emit either blue or UVlight because of the efficiency of LEDs emitting in these wavelengthranges. In addition, different phosphor layers may be applied ondifferent chips on the same submount. The submount may be ceramic orother appropriate material. The submount typically includes electricalcontact pads on a bottom surface that are coupled to contacts on themourning board 164. Alternatively, electrical bond wires may be used toelectrically connect the chips to s mounting board. Along withelectrical contact pads, the LEDs 162 may include thermal contact areason the bottom surface of the submount through which heat generated bythe LED chips can be extracted. The thermal contact areas are coupled toheat spreading layers on the mounting board 164. Heat spreading layersmay be disposed on any of the top, bottom, or intermediate layers ofmounting board 164. Heat spreading layers may be connected by vias thatconnect any of the top, bottom, and intermediate heat spreading layers.

In some embodiments, the mounting board 164 conducts heat generated bythe LEDs 162 to the sides of the board 164 and the bottom of the board164. In one example, the bottom of mounting board 164 may be thermallycoupled to a heat sink, or a lighting fixture and/or other mechanisms todissipate the heat, such as a fan. In some embodiments, the mountingboard 164 conducts heat to a heat sink thermally coupled to the top ofthe board 164. Mounting board 164 may be an FR4 board, e.g., that is 0.5mm thick, with relatively thick copper layers, e.g., 30 micrometers to100 micrometers, on the top and bottom surfaces that serve as thermalcontact areas. In other examples, the board 164 may be a metal coreprinted circuit board (PCB) or a ceramic submount with appropriateelectrical connections. Other types of boards may be used, such as thosemade of alumina (aluminum oxide in ceramic form), or aluminum nitride(also in ceramic form).

Mounting board 164 includes electrical pads to which the electrical padson the LEDs 162 are connected. The electrical pads are electricallyconnected by a metal, e.g., copper, trace to a contact, to which a wire,bridge or other external electrical source is connected. In someembodiments, the electrical pads may be vias through the board 164 andthe electrical connection is made on the opposite side, i.e., thebottom, of the board. Mounting board 164, as illustrated, is rectangularin dimension. LEDs 162 mounted to mounting board 164 may be arranged indifferent configurations on rectangular mounting board 164. In oneexample LEDs 162 are aligned in rows extending in the length dimensionand in columns extending in the width dimension of mounting board 164.In another example, LEDs 162 are arranged in a hexagonally closelypacked structure. In such an arrangement each LED is equidistant fromeach of its immediate neighbors. Such an arrangement is desirable toincrease the uniformity and efficiency of emitted light.

FIGS. 11, 12, and 13 illustrate three exemplary luminaires. Luminaire350 illustrated in FIG. 11 includes an LED based illumination device 300with a rectangular form factor. The luminaire 450 illustrated in FIG. 12includes an LED based illumination device 400 with a circular formfactor. The luminaire 550 illustrated in FIG. 13 includes an LED basedillumination device 500 integrated into a retrofit lamp device. Theseexamples are for illustrative purposes. Examples of LED basedillumination devices of general polygonal and elliptical shapes may alsobe contemplated.

Luminaires 350, 450, and 550 include LED based illumination devices 300,400 and 500, reflectors 302, 402, and 502, and light fixtures 301, 401,and 501, respectively. As depicted, the light fixtures include a heatsink capability, and therefore may be sometimes referred to as a heatsink. However, the light fixtures may include other structural anddecorative elements (not shown). The reflectors are mounted to the LEDbased illumination devices to collimate or deflect light emitted fromeach LED based illumination device. Reflectors may be made from athermally conductive material, such as a material that includes aluminumor copper and may be thermally coupled to each LED based illuminationdevice. Heat flows by conduction through the LED based illuminationdevice and the thermally conductive reflector. Heat also flows viathermal convection over the reflector. Reflectors may be compoundparabolic concentrators, where the concentrator is constructed of orcoated with a highly reflecting material. Optical elements, such as adiffuser or reflector may be removably coupled to an LED basedillumination device, e.g., by means of threads, a clamp, a twist-lockmechanism, or other appropriate arrangement. As illustrated in FIG. 13,the reflector 502 may include sidewalls 503 and a window 504 that areoptionally coated, e.g., with a wavelength converting material,diffusing material or any other desired material.

As depicted in FIGS. 11, 12, and 13, the LED based illumination deviceis mounted to a heat sink. The heat sink may be made from a thermallyconductive material, such as a material that includes aluminum or copperand may be thermally coupled to an LED based illumination device. Heatflows by conduction through an LED based illumination device and thethermally conductive heat sink Heat also flows via thermal convectionover the heat sink. Each LED based illumination device may be attachedto a heat sink by way of screw threads to clamp the LED basedillumination device to the heat sink. To facilitate easy removal andreplacement, the LED based illumination device may be removably coupledto the heat sink, e.g., by means of a clamp mechanism, a twist-lockmechanism, or other appropriate arrangement. The LED based illuminationdevice includes at least one thermally conductive surface that isthermally coupled to the heat sink, e.g., directly or using thermalgrease, thermal tape, thermal pads or thermal epoxy. For adequatecooling of the LEDs, a thermal contact area of at least 50 squaremillimeters, but preferably 100 square millimeters should be used perone watt of electrical energy flow into the LEDs on the board. Forexample, in the case when 20 LEDs are used, a 1000 to 2000 squaremillimeter beat sink contact area should be used. Using a larger heatsink may permit the LEDs to be driven at higher power, and also allowsfor different heat sink designs. For example, some designs may exhibit acooling capacity that is less dependent on the orientation of the heatsink. In addition, fans or other solutions for forced cooling may beused to remove the beat from the device. The bottom heat sink mayinclude an aperture so that electrical connections can be made to theLED based illumination device.

Although certain specific embodiments are described above forinstructional purposes, the teachings of this patent document havegeneral applicability and are not limited to the specific embodimentsdescribed above. For example, it is understood that the Bluetooth Smartprotocol and the Bluetooth Low Energy protocol are sometimes referred tointerchangeably in common industry parlance, and their usage asdescribed herein is provided by way of non-limiting example, as manyother wireless communication protocols may be contemplated within thescope of this patent document. Accordingly, various modifications,adaptations, and combinations of various features of the describedembodiments can be practiced without departing from the scope of theinvention as set forth in the claims.

What is claimed is:
 1. A mobile communications device, comprising: oneor more processors; a camera module configured to capture one or moreimages of a plurality of LED based illumination devices within anenvironment; and a non-transitory, computer readable medium storinginstructions that when executed by the one or more processors cause theone or more processors to: identify a presence of the plurality of LEDbased illumination devices based on the one or more images; andcommunicate a signal indicative of at least one light control rule toeach of the plurality of LED based illumination devices, wherein the atleast one light control rule is indicative of a desired lightingresponse of each of the plurality of LED based illumination devices to asignal received from the sensor module indicative of a triggering eventdetected by a sensor module.
 2. The mobile communications device ofclaim 1, wherein the signal is also indicative of a network identity ofthe sensor module and a network identity of each of the plurality of LEDbased illumination devices.
 3. The mobile communications device of claim1, wherein the at least one light control rule includes a parameterdefining any of a fade-on rate, a target intensity level, a persistencetime, and a fade-off rate.